This invention relates to sprinkler heads for discharging fluids in a circular pattern of variable diameter or in a variable size segment of such circular pattern and more particularly to an improved structure for such a sprinkler head which structure has reduced size and is simple and inexpensive to fabricate.
By way of example, the sprinkler head of this invention is particularly suitable for use in permanently installed sprinkler systems for lawns and gardens which are widely used to provide efficient watering of grass, plants and trees. Such sprinkler systems usually include generally horizontal pipes buried in the ground with vertical pipes or risers extending to the surface of the ground at spaced points along the buried pipes and with sprinkler heads on the free ends of the risers to spray or sprinkle water issuing from the risers under pressure over a predetermined area.
The predetermined area covered by such sprinkler head is inherently circular and the distribution of the water within such area tends to be annular. Thus, the sprinkler heads are usually spaced from each other to cover overlapping areas in an attempt to provide an even distribution of water over the area to be covered. However, most lawns and gardens have rectilinear boundaries defining areas that are not circular but have corners and narrow extensions.
Thus, in the prior art, specialized sprinkler heads have been provided, each of which is designed to distribute water over one of a given number of different segments of a circular area. For example, sprinkler heads designed to distribute water over a 1/4, 1/3, 1/2, 2/3 or 3/4 segments of a circle are common. Thus, a total of six or more different sprinkler heads were sometimes required in a given sprinkler system to provide satisfactory water distribution over an irregular area.
It has been proposed in the prior art to make an adjustable sprinkler head capable of being adjusted to distribute water over a selected segment of a circular area. However, such structures have either been excessively large in their dimensions or too complicated and expensive in their construction for universal use particularly in lawn and garden sprinkling systems.
It is the primary object of this invention to provide a single adjustable sprinkler head structure which is not only small enough but also simple and inexpensive enough to be used universally throughout a lawn sprinkling system requiring a number of sprinkler heads certain of which must cover various segments of circular areas and others of which must cover full circular areas.